1. Field of the Invention
The present invention relates to the field of data distribution and, in particular, to the secure distribution and utilization of data, such as, for example, confidential or proprietary documents or audio, video, multimedia or other entertainment content, over a network.
2. Description of Related Art
The ease with which data may be copied and distributed over public and private networks has been a major impediment to the widespread use of networks as a medium for the sale and distribution of data. In particular, the inability to prevent the illegal copying and/or distribution of copyrighted material or the pilfering of proprietary documents has thwarted the commercial use of networks as a viable sales and distribution channel.
In the area of entertainment content, copyright violations have been particularly egregious. The illegal copying and distribution of copyrighted material has gone virtually unchecked, with little recourse to the copyright owners. The recent decision of a federal court to issue an injunction shutting down the song-swapping web site NAPSTER is further indication that, up to the present time, little has be done to prevent illegal copying and distributing over public networks except to prevent use of the network for transmission of copyrighted material altogether. Thus, content owners are still not able to tap the massive markets that exist for online sale and distribution of audio, video, multimedia and other entertainment content.
In addition, the exchange of confidential or proprietary data over public networks such as the Internet, although being tremendously convenient and offering tremendous savings in time and money, has still not been fully embraced by businesses and other networking communities due to concerns over privacy and confidentiality. The ever-present threat of pilfering of such data has prompted many businesses and organizations to recommend that such data be exchanged by means other than an electronic network.
The security, privacy and confidentiality issues associated with data or content distribution over a network have been addressed by several techniques, all with limited success. For example, one of the first techniques to address the distribution of data and content over public networks involved encryption/decryption. In an effort to prevent unauthorized access to data being sent over a network, data may be encrypted in such a manner that it can be decrypted only by the recipient. While this technique may be effective to prevent hacking during transmission of the data, encryption/decryption techniques do nothing to prevent illegal copying and redistribution of the data once the data has been decrypted by the recipient.
Other techniques have sought to prevent illegal copying and distribution of data over networks by identifying the owner of the data within the data itself. For example, certain identifying data, commonly known as a “digital watermark” and deriving its name from a traditional watermark seen on checks and other documents, may be added to data so that the owner, creator, distributor or other interested party may be identified within the data. In addition, a digital watermark may communicate copyright information, such as the owner of the copyright to the data, when the data was first copyrighted, whom the recipient may contact in order to inquire about licensing rights, and the like.
Unfortunately, digital watermarking alone has been insufficient to prevent widespread illegal copying and distributing of copyrighted material. Many in the networking community simply ignore digital watermarks. Moreover, enforcement by copyright owners using digital watermarks alone is tremendously difficult. Even if an unscrupulous user of copyrighted material is aware of a digital watermark, the user can copy and redistribute the data hundreds and even thousands of times without knowledge by the copyright owner. There is little the copyright owner can do to prevent this.
One technique for monitoring the distribution of information that is accessible through a public network is disclosed in U.S. Pat. No. 5,889,860, Encryption System With Transaction Coded Decryption Key. According to the '860 patent, a client who has chosen to purchase online data, such as a song, enters payment information and is assigned a password that is specific to the client and the transaction. The password functions as a decryption key to enable use of the data by the client. Should the client improperly copy and redistribute the data and the decryption password, the copies can be traced back to the client based on client identifying information encoded in the password.
Although possibly effective for identifying clients who have copied and redistributed data, the technique of U.S. Pat. No. 5,889,860 offers no method of enforcement. Similar to the case of digital watermarking, many clients are unconcerned that information identifying them is passed along with the data to unauthorized third parties. As far as the copyright owner is concerned, it is tremendously difficult to determine that data is being copied and redistributed over a public network and, even if it were not difficult, the volume typically associated with the illegal copying and redistributing of popular data is so great that any practical attempts to enforce copyrights would currently be futile.